A high school student whose year of not having a girlfriend is his age, Keiki Kiryuu, suddenly received a love letter. He is happy he can finally have a girlfriend, but is also surprised because not only there is no sender name but also includes a white underwear? The cute girls who gather around him are all weird and with reasons!? Who is the Cinderella who sent the underwear? The mystery called out mystery, even hentai was called out. A new feeling of love comedy that calls out hentei begins!!